Laser induced fluorescence is an established technique for classifying and identifying materials that absorb a particular wavenumber or waveband of radiation. The majority of applications of laser induced fluorescence involve using a pump laser that is matched to an absorption band of the material of interest. The material then fluoresces at a certain wavelength or over a waveband. A spectrometer is used to obtain a spectral fingerprint of the radiation from fluorescence and a grating device or prism is used in the spectrometer to disperse the various wavelengths so that they are spread across a focal plane. However, traditional imaging spectrometers typically require long integration times.
Fizeau interferometers, such as in the form of a multi-aperture telescopes, can also be used in a Fourier Transform Spectroscopic (FTS) mode to acquire high resolution spectral data. However, the Fizeau FTS mode typically requires the collection hundreds of images to in order to obtain the necessary spectral data. The time required to obtain these sets of data can be prohibitive for many applications, especially where it is desirable to quickly identify whether a particular material associated with a particular wavenumber or waveband of radiation is present in a scene.
In view of the above, it is desirable to have a system for quickly and efficiently capturing desired spectral data from a point source and determining the presence of a particular material in the point source that is associated with a particular wavenumber or waveband of radiation.